351 
Bruchmann (7) has investigated a representative of the 
third group of the genus, — ÆEubotrychium. His work on 
B. lunaria shows that there are important difference between 
this subgenus and the other Botrychia. We will describe the 
development of B. simplex and B. neglectum. 
VI Botrychium simplex. 
There is a close similarity in embryological development 
between B. simplex and B. lunaria. The two species seem to 
merge gradually into another; the only real difference being 
the partial coalescence of leaf and fertile spike in B. simplex. 
The eight plants investigated were of very different ages. 
In the youngest plant the second root and the second leaf 
were not yet developed, 
while the oldest plant con- 
sisted of six roots and two 
î leaves, the oldest of which 
— was T4 cm long and bore 
a distinct spoon-shaped la- 
mina. Because of the wide 
Fig. 20. development al range it Fig. 21. 
was possible to treat the 
development of the stele in this plant more fully. Fig. 20 and 21 
show two young plants. The difference from B. obliquumis ver y 
marked. The roots are situated in a plane at right angles to 
that of the cotyledon (as in B. lunaria) instead of being situated 
in the plane of the cotyledon (as in B. obliquum). There are 
very many roots developed and only one visible leaf. 
Position in the Prothallus. The Foot. 
As in some species of Ophioglossum and in B. lunaria the 
very young plant consists practically of a root (see Camp- 
bell (9) and Bruchmann (7)). There is a conspicuous foot 
247 
